Abstract:

In order to study the effect of the microsilica addition on the resistance to explosive spalling of ρ-Al₂O₃ bonded corundum castables,white fused corundum,ρ-Al₂O₃,reactive α-Al₂O₃ micropowder,etc.,were used as the main raw materials,adding microsilica with mass fraction of 0,1%,2%,3%,4%,5% and 6%,respectively,to replace fused white corundum fine powder in the matrix.After vibration casting,the cold mechanical properties,the air permeability,the pore size distribution and the resistance to explosive spalling temperature were tested,respectively.The results show that with the microsilica addition increasing,the cold mechanical properties of the specimens increase,the air permeability after demoulding and drying at 110 ℃ gradually decreases,the air permeability after heat treatment at 1 400 ℃ gradually increases,the overall pore diameter increases,and the resistance to explosive spalling first increases and then decreases.In consideration of the mechanical properties and the resistance to explosive spalling,the optimal microsilica addition is 1%-2%.

Key words: microsilica, ρ-alumina, corundum castables, resistance to explosive spalling

摘要：

为了研究SiO₂微粉添加量对ρ-Al₂O₃结合刚玉质浇注料抗爆裂性能的影响,以电熔白刚玉、ρ-Al₂O₃、活性α-Al₂O₃微粉等为主要原料,分别添加质量分数为0、1%、2%、3%、4%、5%和6%的SiO₂微粉代替基质中的电熔白刚玉细粉,振动浇注成型后,分别检测其常温力学性能、透气度、孔径分布和抗爆裂温度。结果表明:随着SiO₂微粉加入量的增加,试样的常温力学性能增加,脱模后和110 ℃烘后的透气度值逐渐降低,经1 400 ℃热处理后的透气度值逐渐增加,且烧后试样的整体孔径逐渐增大,抗爆裂性能则是先增加后降低。综合考虑试样的力学性能和抗爆裂性能,SiO₂微粉的适宜添加量为1%~2%(w)。

关键词: SiO₂微粉, ρ-Al₂O₃, 刚玉质浇注料, 抗爆裂性